Method for plating with metal oxides

Abstract

A method of plating hydrous metal oxides on at least one substrate, which method is indifferent to the electrochemical properties of the substrate, and comprises reacting metallic ions in aqueous solution with an appropriate oxidizing agent such as sodium hypochlorite or calcium sulfite with oxygen under suitable conditions of pH and concentration such that oxidation and precipitation of metal oxide are sufficiently slow to allow satisfactory plating of metal oxide on the substrate.

What is claimed is: 
     
       1. A method of plating metal oxides on substrates, comprising the steps of: providing a dilute aqueous solution of metal ions which, when oxidized, form metal oxide which is insoluble in water;   providing at least one oxidizing agent which can react with said metal ions to form said metal oxide;   providing at least one substrate onto which said metal oxide is to be deposited; and   mixing said oxidizing agent with said aqueous solution of metal ions under pH and concentration conditions, and at rates sufficiently low, to permit precipitation and adhesion of said oxide to said at least one substrate placed in contact with said aqueous solution thereby causing plating of said oxide on said at least one substrate.   
     
     
       2. The method of claim 1, wherein said metal ions are selected from the group consisting of cobalt, nickel, manganese and mixtures thereof. 
     
     
       3. The method of claim 1, wherein said metal ions are precipitated in combination with at least one other species of metal ion. 
     
     
       4. The method of claim 1, wherein said oxidizing agent is selected from the group consisting of sodium hypochlorite and calcium sulfite. 
     
     
       5. The method of claim 4, wherein said sodium hypochlorite is mixed in solution with boric acid. 
     
     
       6. The method of claim 4, wherein oxygen is present in addition to said calcium sulfite. 
     
     
       7. The method of claim 1, wherein said pH is adjusted using acid or alkalai in order to regulate rate of oxidation. 
     
     
       8. The method of claim 1, wherein said pH is adjusted by altering the ratio of the amount of metal ions to the amount of oxidant. 
     
     
       9. The method of claim 1, wherein the step of providing a dilute aqueous solution of metal ions which, when oxidized, form metal oxide which is insoluble in water, and the step of providing at least one oxidizing agent which can react with said metal ions to form said metal oxide are operated continuously. 
     
     
       10. The method of claim 1, wherein said at least one substrate is substantially a nonconductor of electricity and chemically inert with respect to said plating. 
     
     
       11. The method of claim 1, wherein said at least one substrate is glass.